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arXiv · hep-th/0307034

Thermal Partition Functions for S-branes

Yuji Sugawara
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Abstract

We calculate the thermal partition functions of open strings on the S-brane backgrounds (the bouncing or rolling tachyon backgrounds) both in the bosonic and superstring cases. According to hep-th/0302146, we consider the discretized temperatures compatible with the pure imaginary periodicity of tachyon profiles. The ``effective Hagedorn divergence'' is shown to appear no matter how low temperature is chosen (including zero-temperature). This feature is likely to be consistent with the large rate of open string pair production discussed in hep-th/0209090 and also emission of closed string massive modes hep-th/0303139. We also discuss the possibility to remove the divergence by considering the space-like linear dilaton backgrounds as in hep-th/0306132.

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Yuji Sugawara. 2003-07-15. Thermal Partition Functions for S-branes. https://doi.org/10.1088/1126-6708%2F2003%2F08%2F008

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